Diaphragm structure



Aug. 28, 1923.

- 1,466,243 S. e. NEAL DIAPHRAGM STRUCTURE Filed March 12, 1923 IN V EN TOR Spent I ma-4kg A TTORNE Y5.

Patente Aug. 28, 192 53.

SPENCER G. N, 01 NEW YORK, N. Y.,

BRAKE COMPANY, OF WILMINGTON, DELAWARE, A CORPO ASSIGNOR '10 AUTDMATIC STRAIGHT AIR T1013?! OF DELAWARE. v

DIAPLHBAGM STRUCTURE.

Application filed March 12, 1923. Serial No. 624,478.

To all whom it my comem:

Be it known that I SPENOER'G. NEAL, a citizen of the United States, and resident of the borough of Manhattan, city, county, and State of New York, have invented certain new and useful Improvements in Diaphragm Structures, of which the following is a specification.

It has been found in the practical operation of diaphragms made in accordance withPatent No. 1,062,300 and used in air brake apparatus, that that portion of the diaphragm between the rigid supporting members and the central floating or pulsating supporting members is unduly stressed by the air pressure. In diaphragm structuresmade and used in accordance with the mentioned patent there is a very slight unsupported portion of the diaphragm between the central supporting members and the rigid marginal supporting members and this unsupported portion is apt to be stretched or excessively stressed in the op- 'eration of the air brake apparatus.

It is the main object of this invention to provide a diaphragm structure in which the excessive stress of the unsupported part of the diaphragm will be eliminated. Diaphragm structures of the kind indicated herein must be very sensitive. Usually they are formed of one or more sheets of very thin copper in order to secure the required sensitiveness. It is quite unsatisfactory to strengthen the diaphragm by means of rigidly held strengthening sheets or members.

Such a structure is not sensitive enough and does not respond readil enough to variations in air pressures. n carryin out this invention I employ a freely floating reinforcin or sustaining ring which is arranged to bri ge the gap between the rigid marginal supporting means and the floating or pulsating central supporting means. This fioatin ring is of suflicient width to give ample %)earing surface on both the marginal supporting means and the central supporting means and it is formed with lugs adapted to engage the supporting means to revent undue lateral shifting of the ring.

y this means the sustaining ring is maintained accurately in position to at all times bridge the gap between the rigid and pulsating supports while at the same time offering no resistance to the pulsations of the diaphragm. It is manifest, therefore, that Fig. 2 a similar view showin the diaphragm structure in normal position;

Fig. 3 an enlarged section view of one s1de of thediaphragm and its supporting structure showing the diaphragm deflected from normal position by air ressure;

Fig. 4, a view similar to ig. 3, showing the iaphragm in normal or neutral position; and

Fig. 5 a detail taining ring.

Iii the use of diaphragms made in accordance with Patent Nd-1,062,300 and used in the air brake apparatus as exemplified by Patent No, 1,326,211 dated December 30, 1919, the diaphragm 1, preferably of thin sheet copper of one or more layers, is supported around its marginaledges by rigid supports 2. These supports are usually a part of the structure of the air brake apparatus, which need'not be more specifically described here in. This ri 'd marginal support of the diaphragm is ormed with an inwardly flaring mouth 3, which of course is annular, an permits of a certain limited flexing of the diaphragm, the walls of said mouth receiving and supporting the diaphragm when it is deflected from normal position as indicated in Fig. 1 of the drawing. The central portion of the diaphragm 1s clamped between two central supporting members 4 and 5, said members being usually connected to an operative part of the apparatus as indicated in the said Patent No. 1,326,211, but which need not be illustrated or described herein. The supporting members 4 and 5 are only slightly smaller in diameter than perspective View of the susiaphra the space between the inner marginal edges 'of the stationary supports 2 so that there is only a slight unsupported part of the diaporting member 5 is curved upwardly on its upper bearing surface, and the lower surface of the upper sup orting member 4 is correspondingly curve a slight outwardly this stress and stretching T flaring channel being formed between said supporting members, the outer portion of said channel being slightly greater in width than the thickness of the diaphragm so that the diaphragm may have a slight lateral movement in the outer portion of said cliannel. This is clearly illustrated in Fig. 3 of the drawing.

Tt has been found in the practical oper ation of air brake apparatushavin diaphragms supported as shown in the drawings and as described herein, that the very small unsupported part of the diaphragm around the margin of the inner supporting members is unduly stressed and stretched when air pressure is applied. To avoid insert a bridge ring 6 which extends across the said unsupported part of the diaphragm, a portion of said bridge ring extending into the channel 7 between the two central supportin members and into the channel 3 forme I between the two rigid marginal supporting members.

her 5 and hold terial sidewise 'tain the bridge ring accurately in position.

till) The ring is formed with lugs 8 which are arranged to engage the outer edge of the lower central supporting memthe bridge. ring against ma shifting. These lugs mainto bridge the space between the reciprocating and rigid supporting members while at the same time permitting it to freely float or vibrate with the diaphragm. This bridge ring may be of any desired thickness to resist the air pressures employed in the apparatus,

but it is preferably flexible enough to yield readily under the pressures employed, as indicated in Figs. 1 and 3 of the drawmg.

By providing a floating bridge ring the sensitiveness of the diaphragm is not lnterfered with as the said ring is merely flexed by the air pressure and all tendency to buckle when the diaphragm returns to normal or neutral posit-ion is avoided. Tt is manifest that if a strengthening layer were rigidly clamped between the marginal and central supports it would have a great stif fening effect on the diaphragm and would materially interfere with its sensitiveness and prevent its ready response to variations in air pressure. By means of the floating ring the desired support may be provided for the diaphragm when it is deflected from the normal by air pressure while at the same time the diaphragm as a whole is not stiffened.

Another advantage of the floating bridge ring is that should the diaphragm become gin of said bridge ring being free,

reeaeae broken or ruptured the ring will form a seal and prevent excessive leakage through the diaphragm. The bridge ring will form a seal because its inner and outer margins will be closely pressed against the supports when air pressure is on-the diaphragm, as shown clearly in Fig. 3 of the drawing. Air will leak through the ruptured or broken diaphragm only when the pressure is sufficient to deflect the diaphragm and at that time the bridge ring will be pressed into intimate contact with its supports and will then serve as a support for the diaphragm and as a means for sealing any break therein.

Tn the drawing only one bridg ring is shown for the reason that the diaphragm structure illustrated is designed to receive air pressureon one side. only. As illustrated the bridge ring is under the diaphragm and the air pressure is designed to be placed only on nation of a diaphragm, a rigid marginal support therefor, a movable central support, a bridge-ring extending across the space between said supports and adapted to engage both of said supports when the diaphragm is deflected from its normal position, one margin of said bridge ring being free, and formed with lugs adapted to engage oneof the supports and thereby revent material lateral shifting of the bri ge-ring.

. 3. vTn a diaphragm structure the combination of a diaphragm, a rigid marginal support therefor, a movable central support, a

'bridge-ring extending across the space between said supports and adapted to engage both of said supports when the diaphragm is deflected from its normal position, one mar;

an formed with lugs adapted to engage the margin of one of members and thereby prevent material lateral shifting of the said ring.

Tn testimony whereof T hereunto aflix my signature.

SPENCER Gr. lETEATJ.

the central supporting 

